1. Field of the Invention
Embodiments described herein relate to the field of microsurgical probes. More particularly, embodiments described herein are related to the field of endoscopic Optical Coherence Tomography (OCT) and to the field of ophthalmic microsurgical techniques.
2. Description of Related Art
The field of microsurgical procedures is evolving rapidly. Typically, these procedures involve the use of probes that are capable of reaching the tissue that is being treated or diagnosed. Such procedures make use of endoscopic surgical instruments having a probe coupled to a controller device in a remote console. Current state of the art probes are quite complex in operation, often times requiring moving parts that are operated using complex mechanical systems. In many cases, an electrical motor is included in the design of the probe. Most of the prior art devices have a cost that makes them difficult to discard after one or only a few surgical procedures. Furthermore, the complexity of prior art devices leads generally to probes having cross sections of several millimeters. These probes are of little practical use for ophthalmic microsurgical techniques. In ophthalmic surgery, dimensions of one (1) mm or less are preferred, to access areas typically involved without damaging unrelated tissue.
Scanning mechanisms that allow time-dependent direction of light for diagnostic or therapeutic purposes have been used in endoscopic surgical instruments. These instruments typically use probes that provide imaging, treatment, or both, over an extended area of tissue without requiring motion of the endoscope relative to its surroundings. However, efforts to develop scanning endoprobes compatible with ophthalmic surgery have been slowed by the difficulty of providing the complex drive mechanisms in a compact form factor, at a low cost. This is particularly true for forward-directed scanning probes that may require counter rotating shafts with fixed or controlled relative speeds. For example, a rotation scanning probe is disclosed in U.S. Pat. No. 7,364,543 ('543 patent), incorporated herein by reference in its entirety. In patent '543 two different gear motors are used to counter-rotate tubes in a probe, unnecessarily complicating a probe design and implementation. Furthermore, inefficient use is made of the motor power since each motor is devoted to moving only one element.
Therefore, there is a need for simple and efficient rotational mechanisms for microsurgical probes.